Parasitology Research

, 105:135 | Cite as

Expression of interferon gamma and proinflammatory cytokines in the cecal mucosa of rats experimentally infected with Blastocystis sp. strain RN94-9

  • Aya Iguchi
  • Hisao YoshikawaEmail author
  • Minoru Yamada
  • Isao Kimata
  • Naoki Arizono
Original Paper


Blastocystis hominis is a zoonotic intestinal protozoan parasite whose pathogenic potential is still controversial. The aim of the present study was to clarify the pathogenicity of Blastocystis parasites in rats. Oral inoculation with 1 × 105 cysts of Blastocystis sp. strain RN94-9 in rats resulted in chronic infection in the cecum at least until 4 weeks after infection. Histological examination revealed neither mucosal sloughing nor inflammatory cell infiltration but showed a slight but significant increase in goblet cell numbers in the cecal mucosa 1–3 weeks post-infection. Differential staining of acidic and neutral mucins by the alcian blue–periodic acid-Schiff method showed that the predominantly increased cells were neutral mucin+ but not acidic mucin+ goblet cells. Reverse transcription real-time polymerase chain reaction studies demonstrated significant upregulation of the expression of interferon-γ, interleukin (IL)-12, and tumor necrosis factor alpha, but not IL-6 or granulocyte-macrophage colony-stimulating factor, in the cecal mucosa at 2 and/or 3 weeks post-infection. The induction of local host responses, including mild goblet cell hyperplasia, and significant upregulation of type-1 and proinflammatory cytokines, suggest that Blastocystis sp. strain RN94-9 is a weakly pathogenic organism that could elicit proinflammatory as well as protective responses in local tissues.


Goblet Cell Blastocystis Infection Acidic Mucin Neutral Mucin Host Epithelial Cell 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.



A part of this study was supported in part by a Grant-in-Aid for Scientific Research to H. Y. (C-16590338 and B-17406007).


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Copyright information

© Springer-Verlag 2009

Authors and Affiliations

  • Aya Iguchi
    • 1
  • Hisao Yoshikawa
    • 1
    Email author
  • Minoru Yamada
    • 2
  • Isao Kimata
    • 3
  • Naoki Arizono
    • 2
  1. 1.Department of Biological Sciences, Faculty of ScienceNara Women’s UniversityNaraJapan
  2. 2.Department of Medical ZoologyKyoto Prefectural University of MedicineKyotoJapan
  3. 3.Department of Medical ZoologyOsaka City University Graduate School of MedicineOsakaJapan

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